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Assertions

Lookahead

Bases: RegexComponent

Creates a lookahead assertion.

Regex: (?=...)

Source code in src/pyregexbuilder/assertions.py 
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class Lookahead(RegexComponent):
    """
    Creates a lookahead assertion.

    Regex: `(?=...)`
    """

    def __init__(self, *components: str | RegexComponent) -> None:
        self._regex = rf"(?={self.parse(*components)})"

NegativeLookahead

Bases: RegexComponent

Creates a negative lookahead assertion.

Regex: (?!...)

Source code in src/pyregexbuilder/assertions.py 
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class NegativeLookahead(RegexComponent):
    """
    Creates a negative lookahead assertion.

    Regex: `(?!...)`
    """

    def __init__(self, *components: str | RegexComponent) -> None:
        self._regex = rf"(?!{self.parse(*components)})"

NegativeLookbehind

Bases: RegexComponent

Creates a negative lookbehind assertion.

Regex: (?<!...)

Source code in src/pyregexbuilder/assertions.py 
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class NegativeLookbehind(RegexComponent):
    """
    Creates a negative lookbehind assertion.

    Regex: `(?<!...)`
    """

    def __init__(self, *components: str | RegexComponent) -> None:
        self._regex = rf"(?<!{self.parse(*components)})"

PositiveLookbehind

Bases: RegexComponent

Creates a positive lookbehind assertion.

Regex: (?<=...)

Source code in src/pyregexbuilder/assertions.py 
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class PositiveLookbehind(RegexComponent):
    """
    Creates a positive lookbehind assertion.

    Regex: `(?<=...)`
    """

    def __init__(self, *components: str | RegexComponent) -> None:
        self._regex = rf"(?<={self.parse(*components)})"